The present invention relates to a structure having a movable panel.
In structures of this type it is known to use slidable or rollable devices to transfer a movable panel out of a flush-fitting plane into a parallel non-flush plane and to move the panel in a lateral manner such that an opening in the structure is presented. The known means for transferring the panel between planes may be provided by sets of slidable extension devices mounted perpendicular to the panel and positioned at the top and bottom thereof, and at additional intermediate positions for large panels. There is no quarantee of simultaneous movement of the extension devices since even movement of the panel is difficult and may be impossible with large panels. This may result in excessive stresses in the panel and any means allowing lateral movement thereof such that operation becomes difficult.
It is obvious that when the panel is required to be angled to the vertical when closed, e.g. for a glazed structure, the bearing surfaces or slides of the extension devices must be maintained horizontal in order to avoid the effect of gravity increasing the force required to transfer the panel between the flush-fitting and the non-flush planes. Difficulties are known to arise concerning the arrangement of the wheels or rollers of the devices used for lateral movement. particularly with regard to the angle of contact between the track and the rollers engageable therewith.
It is also a feature of known panelled structures that at least one internal frame is used to which the sets of slidable extension devices may be attached. Side panels may also be attached thereto.